How to use the datapackage.helpers.ensure_dir function in datapackage

def test_ensure_dir():
    base_path = tempfile.mkdtemp()
    try:
        dir_path = os.path.join(base_path, 'dir')
        file_path = os.path.join(dir_path, 'file')
        assert not os.path.isdir(dir_path)
        helpers.ensure_dir(file_path)
        assert os.path.isdir(dir_path)
    finally:
        shutil.rmtree(base_path)

# Get storage
    plugin = import_module('jsontableschema.plugins.%s' % backend)
    storage = plugin.Storage(**backend_options)

    # Iterate over tables
    resources = []
    for table in storage.buckets:

        # Prepare
        schema = storage.describe(table)
        base = os.path.dirname(descriptor)
        path, name = _restore_path(table)
        fullpath = os.path.join(base, path)

        # Write data
        helpers.ensure_dir(fullpath)
        with io.open(fullpath, 'wb') as file:
            model = Schema(deepcopy(schema))
            data = storage.iter(table)
            writer = csv.writer(file, encoding='utf-8')
            writer.writerow(model.headers)
            for row in data:
                writer.writerow(row)

        # Add resource
        resource = {'schema': schema, 'path': path}
        if name is not None:
            resource['name'] = name
        resources.append(resource)

    # Write descriptor
    mode = 'w'

writer.writerow(row)

        # Add resource
        resource = {'schema': schema, 'path': path}
        if name is not None:
            resource['name'] = name
        resources.append(resource)

    # Write descriptor
    mode = 'w'
    encoding = 'utf-8'
    if six.PY2:
        mode = 'wb'
        encoding = None
    resources = _restore_resources(resources)
    helpers.ensure_dir(descriptor)
    with io.open(descriptor,
                 mode=mode,
                 encoding=encoding) as file:
        descriptor = {
            'name': datapackage_name,
            'resources': resources,
        }
        json.dump(descriptor, file, indent=4)
    return storage

# Save resource to storage
        if storage is not None:
            if self.tabular:
                self.infer()
                storage.create(target, self.schema.descriptor, force=True)
                storage.write(target, self.iter())

        # Save descriptor to json
        else:
            mode = 'w'
            encoding = 'utf-8'
            if six.PY2:
                mode = 'wb'
                encoding = None
            helpers.ensure_dir(target)
            with io.open(target, mode=mode, encoding=encoding) as file:
                json.dump(self.__current_descriptor, file, indent=4)

sources.append(source)
            schemas = list(map(_slugify_foreign_key, schemas))
            storage.create(buckets, schemas, force=True)
            for bucket in storage.buckets:
                source = sources[buckets.index(bucket)]
                storage.write(bucket, source())
            return storage

        # Save descriptor to json
        elif str(target).endswith('.json'):
            mode = 'w'
            encoding = 'utf-8'
            if six.PY2:
                mode = 'wb'
                encoding = None
            helpers.ensure_dir(target)
            with io.open(target, mode=mode, encoding=encoding) as file:
                json.dump(self.__current_descriptor, file, indent=4)

        # Save package to zip
        else:
            try:
                with zipfile.ZipFile(target, 'w') as z:
                    descriptor = json.loads(json.dumps(self.__current_descriptor))
                    for index, resource in enumerate(self.resources):
                        if not resource.name:
                            continue
                        if not resource.local:
                            continue
                        path = os.path.abspath(resource.source)
                        basename = resource.descriptor.get('name')
                        resource_format = resource.descriptor.get('format')